U.S. Pat. No. 4,805,209 entitled "Coordinated Transfer of Voice and Information Through a Digital Switch" discloses method and apparatus for coordinating the transfer of a telephone call and information associated with the telephone call in a call center environment wherein: (a) a digital switch such as, for example, a ROLM Systems CBX which is manufactured by ROLM Systems of Santa Clara, Ca. manages a plurality of telephones; (b) a host applications processor such as, for example, an IBM 370 manages a plurality of display terminals; and (c) telephone calls are transferred among display terminals and telephones associated with the telephone calls. The patent discloses method and apparatus wherein a telephone call input to the CBX is transferred among agents which are stationed at various display terminals. The CBX transfers the telephone call among the telephones and the CBX transfers information pertaining to the telephone call to the host applications processor, which information is used by the host applications processor to display relevant information concerning the call to the appropriate agent. As a result, in this environment, the host applications processor can move information pertaining to a caller from one agent's screen to another agent's screen to coordinate with the voice portion of the call being transferred from the one agent's telephone to the another agent's telephone.
While the above-described method and apparatus suffices in a call center environment wherein a multiplicity of agents are served by a single host applications processor, it does not provide proper operation in a call center environment wherein a switch, such as the CBX switch referred to above, may interact simultaneously with a multiplicity of different host applications processors for performing a multiplicity of different call center functions for various groups of agents. It is important to note that such an environment will exist even in a single business enterprise. This occurs because, typically, even a single business enterprise provides its customers with a multiplicity of different call center services. In such a call center environment, as calls transfer among agents in a business enterprise, a call may involve agents whose terminals interact with host applications processors from different departments. Further, in most cases, these host applications processors cannot communicate with one another and, in fact, these host applications processors have limited knowledge of one another. Still further, in some cases, agents may utilize terminals which are connected to personal computer desktop applications systems such as personal computer desktop systems which are implemented on an IBM PS/2 personal computer.
As a result of the above, there is a need for method and apparatus for permitting host applications processor control links to the switch, such as, for example, the CBX, that permit independent hosts applications processors to tag a call with information which is transferred with the call to identify the caller with application specific information such as, for example, caller account number or an address by which one host applications processor might access further information relating to the caller from another host applications processor.